中强地震密集区与未来强震三要素关系的研究

STUDY ON THE RELATION BETWEEN THE MODERATE EARTHQUAKE CONCENTRATING REGIONS AND THE THREE PARAMETERS OF FUTURE STRONG EARTHQUAKES

系统研究了新疆南北天山地震带内中强地震活动密集区与未来强震三要素之间的关系，试图寻找出适合年度危险区判定的地震活动性背景依据．结果表明：大多数强震均发生在中强地震活动相对密集区内及其边缘，且发生在边缘的概率较大；强震震级的大小与中强地震密集区的尺度有关．中强地震密集区的判别标准为：密集区尺度大于１５０ｋｍ，且其中地震密度（每平方度内地震个数）大于或等于４．最后，就密集区尺度、孕震区尺度、异常区尺度及震源区尺度间的关系进行了讨论．基本结论为：密集区的下限尺度即为孕震区尺度。

In order to locate the dangerous region for annual determination of seismic background,the relationship between the three parameters of future strong earthquakes and the moderate earthquake concentrating regions in the Tianshan seismic zone is analyzed.The results show that most strong quakes occur in the concentrating regions and their borders,especially the borders,and magnitude of strong earthquakes is related to the concentrating region size.The principle of determining the concentrating region is that length of the concentrating region is larger than 150 km and the number of earthquakes in the region is equal to or larger than 4.Further more,the relation among the source size,seismogenic zone size,concentrating region size and anomaly area size is discussed.It is considered that upper and lower limits of the concentrating region size are the anomaly area size and seismogenic zone size respectively.